realistically your only hurting the person that lives there next. Even when it eventually becomes too big a problem to ignore that'll prompt the landlord to hastily cover it up and sell it. And you are also hurting the city pipes as well which costs everyone money.
The landlord will then have to have the drains cleared and hear exactly what they found blocking it. This will improve your relationship with your landlord and they will feel happy that you decided to take revengeful steps against them which don't really serve any purpose and are just a waste of resources. No way are they going to somehow claim back those costs from you
Depends on the country. In Australia, the deposit is held by the government and the landlord needs to apply to get it, which includes showing receipts for any work they had to do. It goes back to the tenant by default. The system in the USA (where the landlord holds the deposit) doesn't make a lot of sense as they aren't really incentivized to return it to the tenant.
Right. I'm all for find a way to tip the balance of power away from the ownership class, but willful damage only screws you. Check your rental contract, a landlord can and will sue you for negligent and purposeful damage to their property. They'll also sing your rental history . Plus, if you're still living there, you're only inconveniencing yourself with the repair process.
Rather than throwing it away, you may have free options for recycling nearby, too. My county has a pretty robust program for residents available with regular recycling and hazardous waste like oil or paint in certain locations. There's sometimes restrictions and sorting required from customers, but it's usually pretty straight forward if you look it up
Don't worry by the way; I know that this is a really bad idea. Source: Every art classroom I've been in has had at least one clogged sink at all times.